You didn't show your code, but since it's the first character which gets corrupted, it reminded of another serial-port example I have, in which the author claimed you need to change the CR to a newline. 
$ob = Device::SerialPort->new($PORT) || die "Can't Open $PORT: $!";

$ob->baudrate(9600)    || die "failed setting baudrate";
$ob->parity("none")    || die "failed setting parity";
$ob->databits(8)       || die "failed setting databits";
$ob->stty_icrnl(1)     || die "failed setting convert cr to new line";
$ob->handshake("none") || die "failed setting handshake";

$ob->write_settings || die "no settings";

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In reply to Re: Losing bytes with Device::SerialPort ? by zentara
in thread Losing bytes with Device::SerialPort ? by Anonymous Monk

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